1. Field of the Invention
The present invention relates to an electrical connector, and particularly to a high density electrical connector having an improved grounding bus.
2. Description of Related Art
With the development of communication and computer technology, high-density electrical connectors with conductive elements in a matrix arrangement are desired to construct a large number of signal transmitting paths between two electronic elements. The high-density electrical connectors are widely used in internal connecting systems of severs, routers and the other like devices requiring high-speed data processing and communication. Such high-density electrical connectors are disclosed in U.S. Pat. Nos. 6,152,747, 6,267,604, 6,171,115, 5,980,321, and 6,299,484. These high-density connectors generally comprise two mating connector halves, i.e., a plug connector half connecting with a backplane and a receptacle connector half connecting with a daughter card and for mating with the plug connector half,.thereby establishing an electrical circuitry between the daughter card and the backplane.
As disclosed in U.S. Pat. Nos. 6,174,202 and 6,171,115, the electrical connectors thereof each include a grounding plate which functions as an Electromagnetic Interference (EMI) shielding to prevent signal terminals of the electrical connector from cross talking, thereby improving stability and reliability of signal transmission of the connector. As well known, electrostatic charges on the connector also adversely affects the stability or reliability of the signal transmission of the connector. However, the prior art does not provide means on the grounding plate which can effectively dissipate the electrostatic charges on the connector through the grounding plate; thus, the problem of an unreliable signal transmission still exists and needs to be resolved.
Hence, a high-density electrical connector with an improved grounding bus is desired to overcome the disadvantages of the prior art.
Accordingly, a first object of the present invention is to provide a high density electrical connector having an improved grounding bus for ensuring reliability and stability of signal transmission.
A second object of the present invention is to provide a high density electrical connector having a plurality of printed circuit substrates therein for electrically connecting two electronic components together.
T o fulfill the above objects, an electrical connector, to be mounted on a mother board, in accordance with the present invention comprises a dielectric frame defining a receiving cavity, a plurality of printed circuit substrates, and a spacer assembled with the printed circuit substrates. The spacer includes a plurality of wafers and defines a plurality of tunnels between every two adjacent wafers for receiving corresponding printed circuit substrates. Each wafer has a dielectric body, a plurality of signal terminals for conductively contacting signal traces of the printed circuit substrate, and a grounding bus covering on the dielectric body. Each grounding bus forms at least one resilient arms conductively contacting with grounding traces formed on the printed circuit substrate before the signal terminals conductively contact the signal traces formed on the printed circuit substrate for removing static remained on the grounding bus.